Capacitive sensing pattern

ABSTRACT

A capacitive input device includes a plurality of receiver sensor electrodes oriented substantially parallel to a first axis proximate to a sensing region of the capacitive input device. The capacitive sensing device also includes a plurality of transmitter sensor electrodes oriented substantially parallel to a second axis proximate to the sensing region and configured to be capacitively coupled with the plurality of receiver sensor electrodes. The at least one receiver sensor electrode of the plurality of receiver sensor electrodes is disposed in a configuration forming multiple crossings with a line that is parallel to the second axis, the multiple crossings occurring proximate to the sensing region.

CROSS-REFERENCE TO RELATED APPLICATIONS (CONTINUATION)

This application is a continuation and claims priority to and benefit ofthe patent application Ser. No. 12/509,385, entitled “Capacitive SensingPattern,” with filing date Jul. 24, 2009, now U.S. Pat. No. 8,237,453and assigned to the assignee of the present application, the disclosureof which is hereby incorporated herein by reference.

BACKGROUND

Capacitive sensing devices are widely used in modern electronic devices.For example, capacitive sensing devices have been employed in music andother media players, cell phones and other communications devices,remote controls, personal digital assistants (PDAs), and the like. Thesecapacitive sensing devices are often used for touch based navigation,selection, or other functions. These functions can be in response to oneor more fingers, styli, other objects, or combination thereof providinginput in the sensing regions of respective capacitive sensing devices.However, there exist many limitations to the current state of technologywith respect to capacitive sensing devices.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and form a part ofthis specification, illustrate embodiments of the technology for atrans-capacitive sensor pattern and, together with the description,serve to explain principles discussed below:

FIG. 1A is a block diagram of an example sensor electrode pattern inaccordance with embodiments of the present technology.

FIG. 1B is a block diagram of a conventional fine pitch sensor alongwith a sensor response to a finger moving along an X-direction.

FIG. 1C is a block diagram of a conventional large pitch sensor alongwith a sensor response to a finger moving along an X-direction.

FIG. 1D is a block diagram of an example sensor electrode pattern alongwith a sensor response to a finger moving along an X-direction inaccordance with embodiments of the present technology.

FIG. 1E is a block diagram of an example sensor electrode pattern alongwith a sensor response to a finger moving along an X-direction inaccordance with embodiments of the present technology.

FIG. 1F is a block diagram of an example sensor electrode pattern alongwith a sensor response to a finger moving along an X-direction inaccordance with embodiments of the present technology.

FIG. 2A is a block diagram of an example sensor electrode in accordancewith embodiments of the present technology.

FIG. 2B is a block diagram of example sensor electrodes in accordancewith embodiments of the present technology.

FIG. 2C is a block diagram of an example sensor electrode pattern inaccordance with embodiments of the present technology.

FIG. 3A is a block diagram of an example sensor electrode of a sensorelectrode pattern in accordance with embodiments of the presenttechnology.

FIG. 3B is a block diagram of an example sensor electrode of a sensorelectrode pattern in accordance with embodiments of the presenttechnology.

FIG. 3C is a block diagram of an example sensor electrode of a sensorelectrode pattern in accordance with embodiments of the presenttechnology.

FIG. 4 is a block diagram of an example sensor electrode pattern inaccordance with embodiments of the present technology.

FIG. 5 is a block diagram of an example sensor electrode pattern coupledwith mutual capacitance sensing circuitry in accordance with embodimentsof the present technology.

FIG. 6 is a flowchart of an example method for detecting multiple inputobjects concurrently disposed in a sensing region of a mutualcapacitance sensor in accordance with embodiments of the presenttechnology.

FIG. 7 is a block diagram of an example sensor electrode pattern coupledwith mutual capacitance sensing circuitry in accordance with embodimentsof the present technology.

The drawings referred to in this description should not be understood asbeing drawn to scale unless specifically noted.

DESCRIPTION OF EMBODIMENTS

Reference will now be made in detail to embodiments of the presenttechnology, examples of which are illustrated in the accompanyingdrawings. While the present technology will be described in conjunctionwith embodiments, it will be understood that the descriptions are notintended to limit the present technology to these embodiments. On thecontrary, the descriptions are intended to cover alternatives,modifications and equivalents, which may be included within the spiritand scope as defined by the appended claims. Furthermore, in thefollowing detailed description, numerous specific details are set forthin order to provide a thorough understanding of embodiments of thepresent technology. However, one of ordinary skill in the art willunderstand that embodiments of the present technology may be practicedwithout these specific details. In other instances, well known methods,procedures, components, and circuits have not been described in detailas not to unnecessarily obscure aspects of the present technology.

Overview of Discussion

Embodiments in accordance with the present technology pertain to amutual capacitance sensing apparatus and its usage. In one embodiment inaccordance with the present technology, the mutual capacitance sensingapparatus comprising a capacitive sensing pattern enabling the detectionof multiple input objects concurrently disposed in a sensing region. Forexample, the capacitive sensing pattern described herein enablesimproved capacitive sensing of an input object's positioning within thesensing region.

The mutual capacitance sensing apparatus includes a sensing region. Themutual capacitance sensing apparatus is sensitive to input by one ormore input objects (e.g. fingers, styli, etc.), such as the position ofan input object within the sensing region. “Sensing region” as usedherein is intended to broadly encompass any space above, around, inand/or near the input device in which sensor(s) of the input device isable to detect user input. In a conventional embodiment, the sensingregion of an input device extends from a surface of the sensor of theinput device in one or more directions into space until signal-to-noiseratios prevent sufficiently accurate object detection. The distance towhich this sensing region extends in a particular direction may be onthe order of less than a millimeter, millimeters, centimeters, or more,and may vary significantly with the type of sensing technology used andthe accuracy desired. Thus, embodiments may require contact with thesurface, either with or without applied pressure, while others do not.Accordingly, the sizes, shapes, and locations of particular sensingregions may vary widely from embodiment to embodiment.

Sensing regions with rectangular two-dimensional projected shape arecommon, and many other shapes are possible. For example, depending onthe design of the sensor array and surrounding circuitry, shielding fromany input objects, and the like, sensing regions may be made to havetwo-dimensional projections of other shapes. Similar approaches may beused to define the three-dimensional shape of the sensing region. Inputobjects in the sensing region may interact with the mutual capacitancesensing apparatus.

For example, sensor electrodes of the input device may use arrays orother patterns of sensor electrodes to support any number of sensingregions. As another example, the sensor electrodes may use capacitivesensing technology in combination with resistive sensing technology tosupport the same sensing region or different sensing regions. Examplesof the types of technologies that may be used to implement the variousembodiments of the invention may be found in U.S. Pat. Nos. 5,543,591,5,648,642, 5,815,091, 5,841,078, and 6,249,234.

As another example, some capacitive implementations utilizetranscapacitive sensing methods based on the capacitive coupling betweensensor electrodes. Transcapacitive sensing methods are sometimes alsoreferred to as “mutual capacitance sensing methods.” In one embodiment,a transcapacitive sensing method operates by detecting the electricfield coupling one or more transmitting electrodes with one or morereceiving electrodes. Proximate objects may cause changes in theelectric field, and produce detectable changes in the transcapacitivecoupling. Sensor electrodes may transmit as well as receive, eithersimultaneously or in a time multiplexed manner. Sensor electrodes thattransmit are sometimes referred to as the “transmitting sensorelectrodes,” “driving sensor electrodes,” “transmitters,” or“drivers”—at least for the duration when they are transmitting. Othernames may also be used, including contractions or combinations of theearlier names (e.g. “driving electrodes” and “driver electrodes.” Sensorelectrodes that receive are sometimes referred to as “receiving sensorelectrodes,” “receiver electrodes,” or “receivers”—at least for theduration when they are receiving. Similarly, other names may also beused, including contractions or combinations of the earlier names. Inone embodiment, a transmitting sensor electrode is modulated relative toa system ground to facilitate transmission. In another embodiment, areceiving sensor electrode is not modulated relative to system ground tofacilitate receipt.

In one embodiment in accordance with the present technology, thecapacitive sensing pattern includes a plurality of receiver sensorelectrodes oriented along an x axis proximate to a sensing region and aplurality of transmitter sensor electrodes oriented along a y axisproximate to the sensing region. At least one of the receiver sensorelectrodes forms multiple crossings with a line that is parallel to they axis. This is in contrast to the common sensor electrode patterns inwhich a sensor electrode of a matrix of straight sensor electrodesoriented along an x axis forms only a single crossing with a line thatis parallel to the y axis.

Furthermore, at least two of the plurality of receiver sensor electrodesor at least two of the plurality of transmitter sensor electrodes areinterleaved with each other. The term “interleaved” refers to occupyingthe boundary space of another. For example, a U-shaped transmittersensor electrode may be inverted and a portion of the inverted U of theU-shaped transmitter sensor electrode may be positioned between the twoopen-ended portions of another U-shaped transmitter sensor electrode. Inother words, “interleaved” may be referred to in the context of sensorelectrodes as a sensor electrode filling a two-dimensional fillablespace provided by another sensor electrode.

Each crossing of a sensor electrode oriented along a first axis and asensor electrode oriented along a second axis constitutes a “pixel”. Ateach pixel, the mutual capacitance between the sensor electrode orientedalong a first axis and the sensor electrode oriented along the secondaxis may be measured, resulting in a “pixel capacitance”. The pixelcapacitance may be perturbed by the presence of an input object, such asa finger, near the pixel, resulting in a signal referred to as the“pixel capacitance change” or ΔC_(t).

Common sensor electrode patterns including transmitter and receiversensor electrodes have a limited ability to accurately detect thepresence of input objects. One example of a common sensor electrodepattern is shown in FIG. 1B. FIG. 1B shows a fine pitch sensor and asensor response to a finger moving along the X-direction. Receiversensor electrodes 130 a, 130 b and 130 c are shown. Transmitter sensorelectrodes 125 a, 125 b, 125 c, 125 d and 125 e (hereinafter, “sensorelectrodes 125 a-125 e”) are also shown. The pitch of a sensor refers tothe distance between the electrodes. As such, the pitch of the receiverand transmitter electrodes determines the arrangement of the pixels,specifically the distance between a pixel and any other neighboringpixel.

The response graph in FIG. 1B shows signal peaks 135 a, 135 b and 135 cdirectly below the corresponding receiver sensor electrodes 130 a, 130 band 130 c, respectively. Signal peaks 135 a, 135 b and 135 c representthe peak signal carried by receiver sensor electrodes 130 a, 130 b and130 c, respectively. As a finger moves from the left to the right alongthe X-direction, it passes over receiver sensor electrode 130 a andreceiver sensor electrode's 130 a crossings over at least one of sensorelectrodes 125 a-125 e. A peak signal 135 a carried by receiver sensorelectrode 130 a is shown in the graph directly below the middle ofreceiver electrode 130 a. As the finger continues to move further to theright along the X-direction, it passes over the pitch between receiversensor electrode 130 a and receiver sensor electrode 130 b.

As the finger continues to move from the left to the right along theX-direction, it passes over receiver sensor electrode 130 b and receiversensor electrode's 130 crossing over at least one of sensor electrodes125 a-125 e. A peak signal 135 b carried by receiver sensor electrode130 b is shown in the graph directly below the middle of receiverelectrode 130 b. Of significance, there is shown an overlap 144 abetween the two graphed lines associated with peak signals 135 a and 135b. Overlap 144 a of the signals occurs significantly above the noisefloor 142.

Continuing on with the description of FIG. 1B, as the finger continuesto move further to the right along the X-direction, it passes over thepitch between receiver sensor electrode 130 b and receiver sensorelectrode 130 c. As the finger continues still to move further to theright along the X-direction, it passes over receiver sensor electrode130 c and receiver sensor electrode's 130 c crossing over at least oneof sensor electrodes 125 a-125 e. A peak signal 135 c carried byreceiver sensor electrode 130 c is shown in the graph directly below themiddle of receiver electrode 130 c. Of significance, there is shown anoverlap 144 b between the two graphed lines associated with peak signals135 b and 135 c. Overlap 144 b of the signals occurs significantly abovethe noise floor 142.

In contrast, FIG. 1C shows a large pitch sensor and a sensor response toa finger moving along an X-direction. In FIG. 1C, to create this “largepitch sensor”, the distance between receiver sensor electrodes 130 a,130 b and 130 c is increased as compared to the distance betweenreceiver sensor electrodes 130 a, 130 b and 130 c of FIG. 1B. In FIG.1C, only transmitter sensor electrodes 125 a, 125 b and 125 c are shown.As a finger moves from the left to the right along the X-direction, itpasses over receiver sensor electrode 130 a and receiver sensorelectrode's 130 a crossing over at least one of sensor electrodes 125 a,125 b and 125 c. A peak signal 135 d carried by receiver sensorelectrode 130 a is shown in the graph directly below the middle ofreceiver electrode 130 a. As the finger continues to move further to theright along the X-direction, it passes over the pitch between receiversensor electrode 130 a and receiver sensor electrode 130 b.

As the finger continues to move from the left to the right along theX-direction, it passes over receiver sensor electrode 130 b and receiversensor electrode's 130 b crossing over at least one of transmittersensor electrodes 125 a, 125 b and 125 c. A peak signal 135 e carried byreceiver sensor electrode 130 b is shown in the graph directly below themiddle of receiver electrode 130 b. Of significance, there is no overlapbetween the two graphed lines associated with peak signals 135 d and 135e. The lack of overlapping indicates that the signals from theneighboring sensors associated with peak signals 135 d and 135 e in theinterpolation area are near noise floor 142.

The interpolation area refers to the location of the finger when it isbetween signal peaks. In order to determine the precise location of thefinger in this area, at least two signals (e.g. 135 d and 135 e arenecessary) although it is common to use more than two signal values todetermine finger position. However, unlike in FIG. 1B where overlaps 144a and 144 b occur above the noise floor 142, the larger pitch of thesensor in FIG. 1C result in that any overlaps occur below the noisefloor, if at all. The interpolation calculation necessary to determinethe position of the finger between receiver sensor electrodes 130 a and130 b in FIG. 1C is therefore highly erroneous.

Continuing on with the description of FIG. 1C, as the finger continuesto move further to the right along the X-direction, it passes over thepitch between receiver sensor electrode 130 b and receiver sensorelectrode 130 c. As the finger continues still to move further to theright along the X-direction, it passes over receiver sensor electrode130 c and receiver sensor electrode's 130 c crossing over at least oneof sensor electrodes 125 a, 125 b and 125 c. A peak signal 135 f carriedby receiver sensor electrode 130 c is shown in the graph directly belowthe middle of receiver electrode 130 c.

Of significance, there is no overlap between the two graphed linesassociated with peak signals 135 e and 135 f, thereby indicating thatthe signals of neighboring sensors in the interpolation area is nearnoise floor 142. Again, unlike in FIG. 1B where overlaps 144 a and 144 boccurred above the noise floor 142, the larger pitch of the sensor inFIG. 1C results in that any overlaps occur below the noise floor, if atall. The interpolation calculation necessary to determine the positionof the finger between receiver sensor electrodes 130 b and 130 c in FIG.1C is highly erroneous. Thus, increasing the pitch between sensorelectrodes results in a loss of accuracy because the ΔC_(t) associatedwith the input object and any group of pixels nearest to the inputobject becomes less pronounced.

To resolve the situation above in which the interpolation calculation ishighly erroneous due to the increase in pitch, the sensor pattern needsto be changed in such a way that the contribution of the neighboringelectrodes in the interpolation area becomes significantly greater thannoise floor 142. For example, FIG. 1D is an example of a capacitivesensing pattern in accordance with embodiments of the present technologyand a sensor electrode response to a finger moving along an X-direction.FIG. 1D shows “U-shaped” receiver sensor electrodes 131 a, 131 b and 131c. Transmitter sensor electrodes 125 a, 125 b, 125 c, 125 d and 125 e(hereinafter, “sensor electrodes 125 a-125 e”) are also shown.

The response graph in FIG. 1D shows signal peaks 136 a, 136 b and 136 cdirectly below the corresponding U-shaped receiver sensor electrodes 131a, 131 b and 131 c, respectively. Signal peaks 136 a, 136 b and 136 crepresent the peak signal carried by receiver sensor electrodes 131 a,131 b and 131 c, respectively. As a finger moves from the left to theright along the X-direction, it passes over receiver sensor electrode131 a and receiver sensor electrode's 131 a two crossings over at leastone of sensor electrodes 125 a-125 e. A peak signal 136 a carried byreceiver sensor electrode 131 a is shown in the graph directly below themiddle of receiver electrode 131 a. As the finger continues to movefurther to the right along the X-direction, it passes over the pitchbetween receiver sensor electrode 131 a and receiver sensor electrode131 b.

As the finger continues to move from the left to the right along theX-direction, it passes over receiver sensor electrode 131 b and receiversensor electrode's 131 b two crossings over at least one of sensorelectrodes 125 a-125 e. A peak signal 136 b carried by receiver sensorelectrode 131 b is shown in the graph directly below the middle ofreceiver electrode 131 b. Of significance, there is shown an overlap 144a between the two graphed lines associated with peak signals 136 a and136 b. Overlap 144 a of the signals occurs significantly above the noisefloor 142.

Continuing on with the description of FIG. 1D, as the finger continuesto move further to the right along the X-direction, it passes over thepitch between receiver sensor electrode 131 b and receiver sensorelectrode 131 c. As the finger continues still to move further to theright along the X-direction, it passes over receiver sensor electrode131 c and receiver sensor electrode's 131 c two crossings over at leastone of sensor electrodes 125 a-125 e. A peak signal 136 c carried byreceiver sensor electrode 131 c is shown in the graph directly below themiddle of receiver electrode 131 c. Of significance, there is shown anoverlap 144 b between the two graphed lines associated with peak signals136 b and 136 c. Overlap 144 b of the signals occurs significantly abovethe noise floor 142.

It should be appreciated that the sensor pattern described in FIG. 1D isan improvement over the sensor pattern described in FIGS. 1B and 1C. Thesensor pattern of FIG. 1D enables better detection of an input objectdue to the greater overlap between the sensor signals 136 a, 136 b and136 c, when compared to areas of overlap between sensor signals 135 a,135 b and 135 c shown in FIG. 1B. It should also be appreciated that thesensor electrode pitch shown FIG. 1D is greater than that of FIG. 1B andrelatively comparable to the sensor electrode pitch of FIG. 1C. Thus,not only does the sensor pattern in FIG. 1D improve signal response whenthe sensor pitch is unchanged, as compared to FIG. 1B, but also providesa sensor response that is above the noise floor when the sensorelectrode pitch is relatively comparable to the sensor electrode pitchshown in FIG. 1C.

FIG. 1E shows a sensor pattern and a sensor response to a finger movingalong an X-direction. In FIG. 1E, the distance between receiver sensorelectrodes 131 a, 131 b and 131 c is increased as compared to thedistance between receiver sensor electrodes 131 a, 131 b and 131 c ofFIG. 1D. In FIG. 1E, only transmitter sensor electrodes 125 a, 125 b and125 c are shown. As a finger moves from the left to the right along theX-direction, it passes over receiver sensor electrode 131 a and receiversensor electrode's 131 a crossing over at least one of sensor electrodes125 a, 125 b and 125 c. A peak signal 136 d carried by receiver sensorelectrode 131 a is shown in the graph directly below the middle ofreceiver electrode 131 a. As the finger continues to move further to theright along the X-direction, it passes over the pitch between receiversensor electrode 131 a and receiver sensor electrode 131 b.

As the finger continues to move from the left to the right along theX-direction, it passes over receiver sensor electrode 131 b and receiversensor electrode's 131 b crossing over at least one of transmittersensor electrodes 125 a, 125 b and 125 c. A peak signal 136 e carried byreceiver sensor electrode 131 b is shown in the graph directly below themiddle of receiver electrode 131 b. Of significance, there is no overlapbetween the two graphed lines associated with peak signals 136 d and 136e. The lack of overlap indicates that the signals from the neighboringsensors associated with peak signals 136 d and 136 e in theinterpolation area are near noise floor 142. In order to determine theprecise location of the finger in the interpolation area, at leastsignals 136 d and 136 e are necessary. However, unlike in FIG. 1D whereoverlaps 144 a and 144 b occur above the noise floor 142, the largerpitch of the sensor in FIG. 1E result in that any overlaps occur belowthe noise floor, if at all. The interpolation calculation necessary todetermine the position of the finger between receiver sensor electrodes131 a and 131 b in FIG. 1C is therefore highly erroneous.

To resolve the situation above in which the interpolation calculation ishighly erroneous due to the increase in pitch, the sensor pattern needsto be changed in such a way that the contribution of the neighboringelectrodes in the interpolation area becomes significantly greater thannoise floor 142.

FIG. 1F comprises receiver sensor electrodes 130 a, 145 and 130 b, whichare interleaved and cross transmitter sensor electrodes 125 a, 125 b and125 c. Signal peaks 150 a, 150 b and 150 c correspond with the middleportion of receiver sensor electrodes 130 a, 145 and 130 b,respectively. These middle portions are of a greater width than anyother portion of the same receiver sensor electrode. Signal peaks 155 aand 160 a, 160 b and 160 d, and 160 c and 155 b correspond with thethinner outer portions of receiver sensor electrodes 130 a, 145 and 130c, respectively.

Of note, the signal peaks 150 a, 150 b and 150 c corresponding to thewider middle portions of receiver sensor electrodes 130 a, 145 and 130b, respectively, are greater than the signal peaks 155 a and 160 a, 160b and 160 d, and 160 c and 155 b corresponding to the thinner outerportions of receiver sensor electrodes 130 a, 145 and 130 b,respectively. Also of note, it is not necessary for the any portion of asensor electrode to be of a different width than any other portion ofthe same electrode. It is important to note that the signal responsefrom a sensor electrode of a similar shape as 130 a, 145 and 130 b yetwith a constant width throughout would still exhibit a similar signalresponse, specifically, a higher signal when an input object is directlyover the middle of the electrode.

Referring still to FIG. 1F, as a finger moves from the left to the rightalong the X-direction, it passes over receiver sensor electrode 130 aand receiver sensor electrode's 130 a three crossings over at least oneof sensor electrodes 125 a, 125 b and 125 c. A signal 155 a carried bythe left outer portion of receiver sensor electrode 130 a is shown inthe graph directly below the left outer portion of receiver sensorelectrode 130 a. As the finger continues to move further to the rightalong the X-direction, it passes over the middle portion of receiversensor electrode 130 a and receiver sensor electrode's 130 a secondcrossings over at least one of transmitter sensor electrodes 125 a, 125b and 125 c. A signal 150 a carried by the middle portion of receiversensor electrode 130 a is shown in the graph directly below the middleportion of receiver sensor electrode 130 a.

As the finger continues to move from the left to the right along theX-direction, it passes over the left outer portion of receiver sensorelectrode 145 and receiver sensor electrode's 145 first crossings overat least one of transmitter sensor electrodes 125 a, 125 b and 125 c. Asignal 160 a carried by the left outer portion of receiver sensorelectrode 145 is shown in the graph directly below the left outerportion of receiver sensor electrode 145. As the finger continues tomove from the left to the right along the X-direction, it passes overthe right outer portion of receiver sensor electrode 130 a and receiversensor electrode's 130 a third crossings over at least one oftransmitter sensor electrodes 125 a, 125 b and 125 c. A signal 160 bcarried by the right outer portion of receiver sensor electrode 130 a isshown in the graph directly below the right outer portion of receiversensor electrode 130 a.

As the finger continues to move from the left to the right along theX-direction, it passes over the middle portion of receiver sensorelectrode 145 and receiver sensor electrode's 145 second crossings overat least one of transmitter sensor electrodes 125 a, 125 b and 125 c. Asignal 150 b carried by the middle portion of receiver sensor electrode145 is shown in the graph directly below the middle portion of receiversensor electrode 145.

Continuing on with the description of FIG. 1F, as the finger continuesto move further to the right along the X-direction, it passes over theleft outer portion of receiver sensor electrode 130 b and receiversensor electrode's 130 b first crossings over at least one oftransmitter sensor electrodes 125 a, 125 b and 125 c. A signal 160 ccarried by the left outer portion of receiver sensor electrode 130 b isshown in the graph directly below left outer portion of receiver sensorelectrode 130 b. As the finger continues to move further to the rightalong the X-direction, it passes over the right outer portion ofreceiver sensor electrode 145 and receiver sensor electrode's 145 thirdcrossings over at least one of transmitter sensor electrodes 125 a, 125b and 125 c. A signal 160 d carried by the right outer portion ofreceiver sensor electrode 145 is shown in the graph directly below rightouter portion of receiver sensor electrode 145.

As the finger continues to move from the left to the right along theX-direction, it passes over the middle portion of receiver sensorelectrode 130 b and receiver sensor electrode's 130 b second crossingsover at least one of transmitter sensor electrodes 125 a, 125 b and 125c. A signal 150 c carried by the middle portion of receiver sensorelectrode 130 b is shown in the graph directly below the middle portionof receiver sensor electrode 130 b. As the finger continues to movefurther to the right along the X-direction, it passes over the rightouter portion of receiver sensor electrode 130 b and receiver sensorelectrode's 130 b third crossings over at least one of transmittersensor electrodes 125 a, 125 b and 125 c. A signal 155 b carried by theright outer portion of receiver sensor electrode 130 b is shown in thegraph directly below right outer portion of receiver sensor electrode130 b.

Significantly and as shown in FIG. 1F, due to the configuration of thecapacitive sensing pattern in which each receiver sensor electrode has aportion in the domain of its neighboring receiver sensor electrode,lines associated with signals overlap significantly above floor noise142. Thus, the capacitive sensing pattern of FIG. 1F which comprisessensor electrodes with a larger pitch than the sensor electrodes in FIG.1D and relatively comparable pitch to FIG. 1E, enables an accurateinterpolation calculation.

It is of note, that the signal responses 135 a-f, 136 a-f, 150 a-c, 155a-b, and 160 a-d of FIGS. 1B-F are shown in a matter as to best explainthe benefits of the sensor design in accordance with the presenttechnology. It should be noted that the signal responses may varysignificantly from the examples described, depending but not limited tothe design of the sensor pattern, the type of sensing scheme used,algorithms used to process the electronic signals, finger size, etc.

The following discussion will begin with a detailed description focusedon aspects of the structure in accordance with the present technology.This discussion will then be followed by a detailed description focusedon aspects of the operation in accordance with the present technology.

Example Capacitive Sensing Pattern in a Mutual Capacitance Sensor

FIG. 1A is a block diagram of an example sensor electrode pattern 100within a mutual capacitance sensor in accordance with embodiments of thepresent technology. In one embodiment, sensor electrode pattern 100comprises a plurality of first sensor electrodes 105 a, 105 b, 105 c,105 d, 105 e, 105 f, 105 g, 105 h and 105 i (hereinafter, “105 a-105 i)oriented along a first axis and a plurality of second sensor electrodes110 a, 110 b, 110 c, 110 d, 110 e, 110 f, 110 g, 110 h, 110 i, 110 j,110 k and 110 l (hereinafter, “110 a-110 l”) oriented along a secondaxis. It should be appreciated that the sensor electrode pattern 100 maycomprise more or less sensor electrodes than those indicated by FIG. 1A.Furthermore, in one embodiment, the plurality of first sensor electrodesmay comprise 110 a-110 l and the plurality of second sensor electrodesmay comprise 105 a-105 i. The plurality of first sensor electrodes 105a-105 i and the plurality of second sensor electrodes 110 a-110 l aredisposed proximate to a sensing region of a mutual capacitance sensor.

In one embodiment, the plurality of first sensor electrodes 105 a-105 iis oriented along a first axis 102. The plurality of second sensorelectrodes 110 a-110 l is oriented along a second axis 104. It should beappreciated that the first axis 102 and the second axis 104 may bepositioned in any direction that is different from each other.

In one embodiment of the present technology, at least one sensorelectrode of the plurality of first sensor electrodes 105 a-105 i isdisposed in a configuration forming multiple crossings with a line thatis parallel to the second axis 104. The term “multiple crossings” refersto more than one point of intersection within a sensing regions betweena sensor electrode oriented substantially parallel to one axis and aline parallel to a second axis, which is substantially non-parallel tothe first axis. For example, sensor electrode 105 d along first axis 102forms multiple crossings with a line that is parallel to the second axis104 (e.g. a line traced substantially along electrode 110 e within thesensing region). These multiple crossings occur proximate to the sensingregion of the mutual capacitance sensor. In one embodiment, at least twoof the plurality of first sensor electrodes 105 a-105 i are interleavedwith each other proximate to the sensing region of the mutualcapacitance sensor.

Moreover, in one embodiment, one of the plurality of first sensorelectrodes 105 a-105 i and the plurality of second sensor electrodes 110a-110 l comprises transmitter sensor electrodes and the other one of theplurality of first sensor electrodes 105 a-105 i and the plurality ofsecond sensor electrodes 110 a-110 l comprises receiver sensorelectrodes. Furthermore, sensing electrode pattern 100 may include arouting trace, shown as 120 as an example of the plurality of routingtraces shown in FIG. 1A to be coupled with the plurality of sensorelectrodes 105 a-105 i.

In one embodiment, the sensor electrode pattern 100 comprises aplurality of receiver sensor electrodes configured to be orientedsubstantially parallel to the first axis 102, wherein at least two ofthe plurality of receiver sensor electrodes are interleaved proximate tothe sensing region of the mutual capacitance sensor. For example, theplurality of first sensor electrodes 105 a-105 i may be receiver sensorelectrodes oriented substantially parallel to the first axis 102. Atleast two, 105 a and 105 b, of the plurality of receiver sensorelectrodes 105 a-105 i are interleaved proximate to the sensing regionsof the mutual capacitance sensor.

In another embodiment, sensor electrode pattern 100 comprises aplurality of transmitter sensor electrodes oriented substantiallyparallel to a second axis and configured to be capacitively coupled withthe plurality of receiver sensor electrodes. For example, the pluralityof sensor electrodes 110 a-110 l may be transmitter sensor electrodesoriented substantially parallel to the second axis 104 and arecapacitively coupled with the receiver sensor electrodes 105 a-105 i.

While FIG. 1A depicts the plurality of first sensor electrodes 105 a-105i as being straight and substantially parallel to each other, it shouldbe appreciated that a portion of the plurality of first sensorelectrodes 105 a-105 i may be positioned in a zig-zagging pattern and besubstantially parallel to each other.

In another embodiment, sensor electrode pattern 100 is configured to beplaced in front of a display (i.e. between the display and a user's lineof sight) such that at least one of the first axis and second axis isangled with respect to the display. In yet another embodiment, sensorelectrode patter 100 may include an optical coating.

FIG. 2A is a block diagram of an example sensor electrode of capacitivesensing pattern 100 in accordance with embodiments of the presenttechnology. In one embodiment, at least one sensor electrode of theplurality of first sensor electrodes 105 a-105 i and the plurality ofsecond sensor electrodes 110 a-110 l has portions of different widths.For example, sensor electrode 105 a of FIG. 2A comprises the portions200, 205 and 210, which are all of different widths. It should beappreciated that a sensor electrode may have some portions of the samewidth and other portions of different widths. For example, in oneembodiment, the portions 200 and 205 may be of the same width and theportion 210 may be of a different width from the portions 200 and 205.

In one embodiment, the sensor electrode 105 a may be referred to as an“intrudable sensor electrode” when at least a portion of sensorelectrode 105 a defines a fillable two-dimensional area. This areaoccurs proximate to the sensing region of the mutual capacitance sensor.For example, the area between the portion 200 and the portion 205constitutes a fillable two-dimensional area. Additionally, in oneembodiment, at least one sensor electrode of the plurality of firstsensor electrodes 105 a-105 i is an intrudable sensor electrode. Ofnote, the sensor electrodes 110 a-110 l of FIG. 1A are shown to bestraight bars for clarity and brevity in the description of embodimentsof the present technology. However, it should be understood that thesensor electrodes 110-110 l may also be configured to be intrudablesensor electrodes like the sensor electrodes 105 a-105 i of FIG. 1A.

Furthermore, as shown in FIG. 2A, in one embodiment, at least oneportion of the intrudable sensor electrode 105 a is of a different widththan another portion of the intrudable sensor electrode 105 a. Forexample, the portion 200 of intrudable sensor electrode 105 a is of adifferent width than the portion 205 of the intrudable sensor electrode105 a.

FIG. 2B is a block diagram of example sensor electrodes of thecapacitive sensing pattern 100 in accordance with embodiments of thepresent technology. In one embodiment, at least two sensor electrodes ofthe plurality of first sensor electrodes 105 a-105 i differ in width orat least two sensor electrodes of the plurality of second sensorelectrodes 110 a-110 l differ in width. For example, FIG. 2B shows thesensor electrodes 105 a and 105 b of the plurality of first sensorelectrodes 105 a-105 i differing in width. The portions 107 a, 107 b and107 c of the sensor electrode 105 a have a different width than theportions 109 a, 109 b and 109 c of the sensor electrode 105 b. It shouldbe appreciated that while FIG. 2B shows the portions 107 a, 107 b and107 c having the same width, 107 a, 107 b and 107 c may have differentwidths (as shown in FIG. 2A). Similarly, while FIG. 2B shows portions109 a, 109 b and 109 c having the same width, 109 a, 109 b and 109 c mayhave different widths (as shown in FIG. 2A).

Furthermore, as already described herein, in one embodiment, a sensorelectrode may be referred to as an “intrudable sensor electrode”. In oneembodiment, and referring still to FIGS. 1A and 2B, at least one sensorelectrode of the plurality of second sensor electrodes 110 a-110 l maybe a second intrudable electrode (not shown in FIG. 1A). However, FIG.2C (described below) shows an example of at least one sensor electrodeof the plurality of second sensor electrodes 110 a-110 l being a secondintrudable sensor electrode.

FIG. 2C is a block diagram of an example capacitive sensing pattern 213in accordance with embodiments of the present technology. The capacitivesensing pattern 213 comprises a plurality of first sensor electrodes 215a, 215 b, 215 c, 215 d and 215 e (hereinafter, “215 a-215 e”) and aplurality of second sensor electrodes 110 a, 110 b, 110 c, 110 d, 110 e,110 f, 110 g, 110 h, 110 i, 110 j, 110 k, 110 l, 110 m, 110 n, 110 o,110 p (hereinafter, “110 a-110 p”). The plurality of second sensorelectrodes 110 a-110 p are intrudable sensor electrodes because eachdefines a fillable two-dimensional area. In one embodiment, some of theplurality of first sensor electrodes 215 a-215 e cover the gaps createdin the interleaved regions of the plurality of second sensor electrodes110 a-110 p while crossing over or under the plurality of second sensorelectrodes 110 a-110 p. For example, sensor electrode 215 a covers allof the gaps created in the interleaved regions along its pathway betweensensor electrodes 110 a and 110 p. However, sensor electrode 215 b doesnot cover any of the gaps created in the interleaved regions along itspathway between the sensor electrodes 110 a and 110 p.

It should be appreciated that the plurality of first sensor electrodes215 a-215 e may be positioned so that all of the plurality of firstsensor electrodes 215 a-215 e cover all of the gaps created in theinterleaved regions along their pathways between the sensor electrodes110 a and 110 p. Additionally, the plurality of first sensor electrodes215 a-215 e may be positioned so that none of the plurality of firstsensor electrodes 215 a-215 e cover any of the gaps created in theinterleaved regions along their pathways between the sensor electrodes110 a and 110 p.

FIG. 3A is a block diagram of an example sensor electrode of acapacitive sensing pattern in accordance with embodiments of the presenttechnology. In one embodiment, capacitive sensing pattern 100 comprisesat least one sensor electrode 105 d of FIG. 1A of the pluralities offirst sensor electrodes 105 a-105 i and the second sensor electrodes 110a-110 l. The sensor electrode 105 d comprises one or more sets of aplurality of extensions. For example, FIG. 3A shows two sets ofextension, 302 and 303. Set of extensions 302 comprises extensions 300a, 300 b, 300 c, 300 d, 300 e and 300 f (hereinafter, “300 a-f”). Set ofextensions 303 comprises extensions 300 g, 300 h, 300 i, 300 j, 300 kand 300 l (hereinafter, “300 g-300 l”). It should be understood thatwhile the set of extensions 302 and 303 are depicted as thin lines,these extensions may be of varying widths.

The plurality of extensions within each set of the one or more sets aresubstantially parallel to each other. For example, the plurality ofextensions 300 a-300 f of set of extensions 302 are substantiallyparallel to each other. In this context, the term “substantiallyparallel” refers to each extension of a plurality of extensions beingpositioned parallel to or close to parallel to each other. Similarly,the plurality of extensions 300 g-300 l of set of extensions 303 aresubstantially parallel to each other. It should be appreciated that setof extensions 300 a-300 f and 300 g-300 l may be positioned at any angleto sensor electrode 105 d. For example, sensor electrode extensions 300a-300 f may be positioned perpendicular to sensor electrode 105 d or atan angle that is non-perpendicular to sensor electrode 105 d.

FIG. 3B is a block diagram of an example sensor electrode of acapacitive sensing pattern, in accordance with embodiments of thepresent technology. As in FIG. 3A, the capacitive sensing pattern ofFIG. 3B comprises at least one sensor electrode 105 d of the pluralitiesof first sensor electrodes 105 a-105 i and second sensor electrodes 110a-110 l of FIG. 1A. The sensor electrode 105 d comprises at least oneextension coupler configured for coupling at least two extensions of theone or more sets of the plurality of extensions 302, thereby providingan area bounded by the sensor electrode 105 d of the pluralities of thefirst and second sensor electrodes, 105 a-105 i and 110 a-110 l,respectively. For example, extension coupler 305 a couples extensions300 b, 300 c and 300 d. Similarly, extension coupler 305 b couplesextensions 300 h, 300 i and 300 j.

The area that is bounded by the sensor electrode 105 d in FIG. 3B, usingthe extension coupler 305 a is the area 310 a. For example, theextensions 300 b and 300 c, a portion of the extension coupler 305 a anda surface 315 of a portion of the sensor electrode 105 d bound area 310a. This bounded area is a gap between portions of the sensor electrode105 d, and can be described as a “window”. Similarly, the extensions 300c and 300 d, a portion of extension coupler 305 a and a surface 320 of aportion of the sensor electrode 105 d bound area 310 b. The extensions300 h and 300 i, a portion of extension coupler 305 b and a surface 325of a portion of the sensor electrode 105 d bound area 310 c. Theextensions 300 i and 300 j, a portion of the extension coupler 305 b anda surface 330 of a portion of the sensor electrode 105 d bound area 310d.

FIG. 3C is a block diagram of an example sensor electrode of acapacitive sensing pattern in accordance with embodiments of the presenttechnology. In one embodiment, the sensor electrode 105 d is a sensorelectrode with three portions, 200, 205 and 210, as is shown in FIG. 2A.The sensor electrode 105 d of FIG. 3C comprises extensions 300 a, 300 b,300 c, 300 d, 300 e, 300 f, 300 g, 300 h, 300 i, 300 j, 300 k and 300 l.However, the extension coupler 305 a couples the extensions 300 b and300 c to form a bounded area 310 e. The extension coupler 305 b couplesthe extensions 300 h and 300 i to form a bounded area 310 f. Theextension couplers 305 c, 305 e and 305 g couple with the extensions 300e and 300 k to form a bounded area 310 g. Similarly, the extensioncouplers 305 d, 305 f and 305 g couple with the extensions 300 f and 300l to form a bounded area 310 h.

It should be understood that the bounded areas and their surroundingextensions and extension couplers may occur in any position relative tosensor electrode 105 d and on any portion of sensor electrode 105 d.Furthermore, it should be understood that extensions and extensioncouplers can be formed to be one and the same feature. Furthermore, aswas described herein, it should be understood that extensions andextension couplers may be embodied as features of receiver and/ortransmitter sensor electrodes.

While FIGS. 3A, 3B and 3C depict extensions that are straight, it shouldbe appreciated that portions of some or all of the extensions may berounded. For example and referring to FIG. 3C, extensions 300 b and 300c may be rounded and meet at their respective ends to form a circularshape that entirely encloses a defined area. In another embodiment,extensions 300 b and 300 c may be rounded, but not meet at theirrespective ends and not entirely enclose a defined area. Furthermore, itshould be appreciated that portions of some or all extension couplersmay also be rounded.

FIG. 4 is a block diagram of an example capacitive sensing pattern 400in accordance with embodiments of the present technology. The capacitivesensing pattern 400 comprises at least two of the plurality of the firstsensor electrodes 105 a, 105 b, 105 c and 105 d (hereinafter, “105 a-105d”) interleaved with each other and at least two of the plurality of thesecond sensor electrodes 405 a, 405 b, 405 c, 405 d, 405 e and 405 f(hereinafter, “405 a-405 f”) interleaved with each other. As describedherein, the term “interleaved” refers to a sensor electrode filling atwo-dimensional fillable space provided by another sensor electrode. Forexample, the sensor electrode 105 a is interleaved with the sensorelectrode 105 b. The portion 430 a of the sensor electrode 105 b fillsthe two dimensional fillable space provided by the portions 425 a and425 b of the sensor electrode 105 a. Similarly, the sensor electrode 405c is interleaved with the sensor electrode 405 d. The portion 440 a ofthe sensor electrode 405 c fills the two dimensional fillable spaceprovided by the portions 435 a and 435 b of the sensor electrode 405 d.Furthermore, the first plurality of the sensor electrodes 105 a-105 dand the second plurality of the sensor electrodes 405 a-405 d comprisefootprint 420.

Of note, the plurality of the first sensor electrodes 105 a-105 d areoriented along the first axis 102. The plurality of the second sensorelectrodes 405 a-405 f are oriented along the second axis 104.Additionally, as is described with reference to FIGS. 2A and 2B,portions of a sensor electrode may be wider than other portions of thatsame sensor electrode. For example, the portion 435 a of the sensorelectrode 405 d is wider than the portions 435 b and 435 c.

In one embodiment and still referring to FIG. 4, at least one sensorelectrode of the plurality of second sensor electrodes 405 a-405 f isdisposed in a configuration forming multiple crossings with a line thatis parallel to the first axis 102. For example, the sensor electrode 405a of the plurality of second sensor electrodes 405 a-405 d formsmultiple crossings, for example crossings at 410 and 415, with a linethat is parallel to the first axis 102.

Referring still to FIG. 4, in yet another embodiment, at least onesensor electrode comprises first and second parallel portionssubstantially along the first axis traversing across most of a footprintof the sensing region, or at least one sensor electrode of the pluralityof second sensor electrodes comprises first and second parallel portionstraversing substantially along the second axis across most of thefootprint. For example, at least one sensor electrode 105 a comprisingthe first 425 a and the second 425 b parallel portions substantiallyalong the first axis 102 traversing across most of the footprint 420 ofthe sensing region or at least one sensor electrode 405 d of theplurality of second sensor electrodes 405 a-405 d comprises the first435 a and the second 435 b portions traversing substantially along thesecond axis 104 across most of the footprint 420.

Referring still to FIG. 4, in one embodiment, the sensor electrode 405 dof the plurality of second sensor electrodes 405 a-405 f has a portion435 a that is wider than the portions 435 b and 435 c of sensorelectrode 405 d. The sensor electrode 405 d is positioned such that aninput object's proximity to the sensor electrode 405 d creates astronger mutual capacitance change in portion 435 a than in the thinnerportions 435 b and 435 c.

In another embodiment, a capacitive sensing pattern may comprise a guardsensor electrode proximate to the pluralities of the first and secondsensor electrodes. For example, the capacitive sensing pattern 400 maycomprise a guard sensor electrode 405 e proximate to the pluralities ofthe first and the second sensor electrodes 105 a-105 d and 405 a-405 d,respectively. It should be noted that a guard electrode 405 e may belocated outside yet proximate to the footprint 420.

FIG. 5 is a block diagram of an example mutual capacitance sensingapparatus 500 comprising mutual capacitance sensing circuitry 515 inaccordance with embodiments of the present technology. Mutualcapacitance sensing apparatus 500 also comprises a plurality of firstsensor electrodes oriented substantially parallel to a first axisproximate to a sensing region of a mutual capacitance sensor and coupledwith mutual capacitance sensing circuitry 515. For example, mutualcapacitance sensing apparatus 500 comprises a plurality of first sensorelectrodes 520 a, 520 b, 520 c, 520 d, 520 e, 520 f, 520 g, 520 h, 520i, 520 j, 520 k and 520 l (hereinafter, “520 a-520 l”) orientedsubstantially parallel to a first axis 102 proximate to a sensing regionof a mutual capacitance sensor and coupled with the mutual capacitancesensing circuitry 515.

The mutual capacitance sensing apparatus 500 also comprises a pluralityof second sensor electrodes oriented substantially parallel to a secondaxis proximate to the sensing region and configured to be capacitivelycoupled with the plurality of first sensor electrodes. For example,mutual capacitance sensing apparatus 500 comprises plurality of secondsensor electrodes 110 a, 110 b, 110 c, 110 d, 110 e, 110 f, 110 g, 110h, 110 i, 110 j, 110 k, 110 l, 110 m, 110 n, 110 o and 110 p(hereinafter, “110 a-110 p”) oriented substantially parallel to a secondaxis 104 proximate to the sensing region and are capacitively coupledwith the plurality of the first sensor electrodes 520 a-520 l.

Further, in one embodiment, at least one sensor electrode of theplurality of first sensor electrodes 520 a-520 l is disposed in aconfiguration forming multiple crossings with a line that is parallel tothe second axis 104, the multiple crossings occurring proximate to thesensing region. Furthermore, one of plurality of first sensor electrodes520 a-520 l and the plurality of second sensor electrodes 110 a-110 pcomprises transmitter sensor electrodes and the other one of pluralityof first sensor electrodes 520 a-520 l and the plurality of secondsensor electrodes 110 a-110 p comprises receiver sensor electrodes.

While FIG. 5 shows that the plurality of first sensor electrodes 520a-520 l are not interleaved with each other and the plurality of secondsensor electrodes 110 a-110 p are not interleaved with each other, itshould be noted that at least two sensor electrodes of the plurality offirst sensor electrodes 520 a-520 l or at least two sensor electrodes ofthe plurality of second sensor electrodes 110 a-110 p may be interleavedwith each other proximate to the sensing region of the mutualcapacitance sensor, such as is shown in FIG. 4 with the plurality offirst sensor electrodes 105 a-105 d and the plurality of second sensorelectrodes 405 a-405 f.

In one embodiment, all of the plurality of first sensor electrodes 520a-520 l or all of the plurality of second sensor electrodes 110 a-110 pare coupled with routing traces 535 a, 535 b, 535 c, 535 d, 535 e, 535f, 535 g, 535 h, 535 i, 535 j, 535 k and 535 l (hereinafter, “535 a-535l”) and 500 a, 500 b, 500 c, 500 d, 500 e, 500 f, 500 g, 500 h, 500 i,500 j, 500 k, 500 l, 500 m, 500 n, 500 o and 500 p (hereinafter, “500a-500 p”), respectively.

In one embodiment, all of routing traces 535 a-535 l associated with aplurality of sensor electrodes oriented along an axis are positioned onone side of the footprint 420. In another embodiment, the routing traces535 a-535 l associated with a plurality of sensor electrodes orientedalong an axis may be positioned on more than one side of the footprint420.

Therefore, embodiments of the present technology enable accuratedetection of input objects when the pitch of the sensor electrodes isincreased.

Operation

In embodiments in accordance with the present technology, the capacitivesensing pattern enables the use of large pitches between sensorelectrodes and more accurate detection of multiple input objectsconcurrently disposed in a sensing region of a mutual capacitancesensor.

FIG. 6 is a flowchart of an example method 600 for detecting multipleinput objects concurrently disposed in a sensing region of a mutualcapacitance sensor in accordance with embodiments of the presenttechnology.

Referring to 605 of FIG. 6 and to FIGS. 1 and 5, in one embodiment,input is received at the mutual capacitance sensing circuitry 515 viathe plurality of first sensor electrodes 520 a-520 l and the pluralityof second sensor electrodes 110 a-110 p. As described herein, theplurality of first sensor electrodes 520 a-520 l are orientedsubstantially parallel to the first axis 102 proximate to a sensingregion of a mutual capacitance sensor and are coupled with the mutualcapacitance sensing circuitry 515. Further, the plurality of secondsensor electrodes 110 a-110 p are oriented substantially parallel to thesecond axis 104 proximate to the sensing region and are configured to becapacitively coupled with the plurality of first sensor electrodes 520a-520 l. At least one sensor electrode of the plurality of first sensorelectrodes 520 a-520 l is disposed in a configuration forming multiplecrossings with a line that is parallel to the second axis 104. Themultiple crossings occur proximate to the sensing region of the mutualcapacitance sensor, wherein at least two of the plurality of firstsensor electrodes 520 a-520 l or at least two of the plurality of secondsensor electrodes 110 a-110 p are interleaved with each other proximateto the sensing region of the mutual capacitance sensor.

The mutual capacitance sensing circuitry 515 receives input in the formof signals when an input object is placed on or proximate to a sensorelectrode of a mutual capacitance sensor. These signals are associatedwith the “pixel capacitance”, C_(t). Mutual capacitance sensingcircuitry 515 then may calculate changes in the value of the “pixelcapacitance” to find the input object's location in a sensing region.

For example and referring to FIG. 7, a block diagram of an examplecapacitive sensing pattern 500 coupled with mutual capacitance sensingcircuitry 515 in accordance with embodiments of the present technologyis shown. Three input objects, 705, 710 and 715 are shown as positionedupon the first plurality of sensor electrodes 520 a-520 l and the secondplurality of sensor electrodes 110 a-110 p. In one embodiment, the firstplurality of sensor electrodes 520 a-520 l are receiver sensorelectrodes, while the second plurality of sensor electrodes 110 a-110 pare transmitter sensor electrodes. However, as described herein, it isunderstood that in another embodiment, the first plurality of sensorelectrodes 520 a-520 l may be transmitter sensor electrodes, while thesecond plurality of sensor electrodes 110 a-110 p may be receiver sensorelectrodes.

In particular, input object 705 is placed on some portion of sensorelectrodes 520 c, 520 d and 520 e as well as 110 j, 110 k and 110 l. Thepixels corresponding to the crossing of the sensor electrode 520 d andthe sensor electrodes 110 k and 110 l show the largest ΔC_(t) since theentire pixel is covered by the input object 705. However, the pixelscorresponding to the crossing of the sensor electrode 520 c and thesensor electrodes 110 k and 110 l show a much smaller ΔC_(t) since onlya portion of the pixels are covered by the input object 705. Likewise,the pixels corresponding to the crossing of the sensor electrode 520 eand the sensor electrodes 110 l and 110 l also show a much smallerΔC_(t) since only a portion of the pixels are covered by the inputobject 705. As explained in FIGS. 1B-F and with reference to the methoddiscussed for interpolating the signal relative to an input object'sproximity to a pixel, the location of the input object 705 can bedetermined to be relatively centered in the region surrounding thepixels with the largest ΔC_(t), and corresponding to the intersection ofthe sensor electrode 520 d and the sensor electrodes 110 k and 110 l.

In one embodiment, the greater the ΔC_(t) measured at a pixel, the morelikely that the mutual capacitance sensing circuitry 515 is to “detect”the cause of the measured ΔC_(t) to be an input object. In anotherembodiment, the mutual capacitance sensing circuitry 515 is configuredto recognize as an input object a pixel with a ΔC_(t) measurement thatis greater than the group of ΔC_(t) measurements of the immediatelysurrounding pixels. The mutual capacitance sensing circuitry 515 may beconfigured to recognize as an input object any number and pattern ofΔC_(t) measurements corresponding to pixels.

Referring still to FIG. 7, input object 710 is placed on some portion ofthe sensor electrodes 520 c, 520 d and 520 e as well as sensorelectrodes 110 f, 110 g and 110 h. The pixels corresponding to thecrossing of the sensor electrode 520 d and sensor electrode 110 g showthe largest ΔC_(t) since the entire pixel is covered by input object710. However, the pixels corresponding to the crossings of the sensorelectrode 520 c and the sensor electrodes 110 f, 110 g and 110 h show amuch smaller ΔC_(t) since only a portion of the pixel are covered by theinput object 710. Likewise, the pixels corresponding to the crossings ofthe sensor electrode 520 e and the sensor electrodes 110 f, 110 g and110 h also show a much smaller ΔC_(t) since only a portion of the pixelsare covered by the input object 710.

Additionally, FIG. 7 shows the input object 715 being placed on someportion of the sensor electrodes 520 g, 520 h and 520 i as well as thesensor electrodes 110 f, 110 g and 110 h. The pixels corresponding tothe crossings of the sensor electrode 520 h and the sensor electrode 110g show the largest ΔC_(t) since the entire pixel is covered by the inputobject 715. However, the pixels corresponding to the crossings of thesensor electrode 520 g and the sensor electrodes 110 g and 110 h show amuch smaller ΔC_(t) since only a portion of the pixels are covered bythe input object 715. Likewise, the pixels corresponding to thecrossings of the sensor electrode 520 i and the sensor electrodes 110 gand 110 h also show a much smaller ΔC_(t) since only a portion of thepixels are covered by the input object 715. The location of the inputobject 715 can be determined to be relatively centered in the regionsurrounding the pixels with the largest ΔC_(t), and corresponding to theintersection of sensor electrode 520 h and sensor electrode 110 g.

Of note, the input objects 705 and 710 are placed on the same receiversensor electrodes 520 c, 520 d and 520 e, while also being placed ondifferent transmitter sensor electrodes. At the same time, the inputobjects 710 and 715 are placed on the same transmitter electrodes 110 f,110 g, and 110 h, while being placed on different receiver electrodes.In order to determine the presence of multiple input objects 705, 710and 715 on the same sensor electrodes, embodiments of the presenttechnology scan the sensing region. Through scanning, the mutualcapacitance sensing circuitry 515 is able to determine the placement ofthe input objects 705, 710 and 715 by the change in the mutualcapacitance between a particular transmitter and receiver sensorelectrode. More specifically, the mutual capacitance sensing circuitry515 is able to determine that a ΔC_(t) occurs due to the placement ofthe input objects 705, 710, and 715 proximate to the sensing region.This information is gathered by the mutual capacitance sensing circuitry515 during frequent scanning of the sensing region. Thus, coordinatesfor each of the input objects 705, 710 and 715 may be determined basedupon the changes in mutual capacitance during the scanning of thesensing region.

The foregoing descriptions of specific embodiments have been presentedfor purposes of illustration and description. They are not intended tobe exhaustive or to limit the present technology to the precise formsdisclosed, and obviously many modifications and variations are possiblein light of the above teaching. The embodiments were chosen anddescribed in order to best explain the principles of the presenttechnology and its practical application, to thereby enable othersskilled in the art to best utilize the present technology and variousembodiments with various modifications as are suited to the particularuse contemplated. It is intended that the scope of the presenttechnology be defined by the claims appended hereto and theirequivalents.

What is claimed is:
 1. A capacitive input device comprising: a pluralityof receiver sensor electrodes oriented substantially parallel to a firstaxis proximate to a sensing region of said capacitive input device; anda plurality of transmitter sensor electrodes oriented substantiallyparallel to a second axis proximate to said sensing region andconfigured to be capacitively coupled with said plurality of receiversensor electrodes; wherein at least one receiver sensor electrode ofsaid plurality of receiver sensor electrodes is disposed in aconfiguration forming multiple crossings with a line that is parallel tosaid second axis, said multiple crossings occurring proximate to saidsensing region.
 2. The capacitive input device of claim 1, wherein theat least one receiver sensor electrode is u-shaped.
 3. The capacitiveinput device of claim 1, wherein the at least one receiver sensorelectrode is configured with a fillable two dimensional area.
 4. Thecapacitive input device of claim 1, wherein the at least one receiversensor electrode is configured with a bounded two dimensional area. 5.The capacitive input device of claim 4, wherein the bounded twodimensional area is formed by the receiver sensor electrode and anextension and an extension coupler.
 6. The capacitive input device ofclaim 1, wherein the at least one receiver sensor electrode comprisesportions of different widths.
 7. The capacitive input device of claim 6,wherein the at least one receiver sensor electrode comprisessubstantially the same width at locations forming said multiplecrossings with a line that is parallel to said second axis.
 8. Acapacitive input device configured to detect multiple input objects in asensing region, said capacitive input device comprising: a plurality offirst sensor electrodes oriented substantially parallel to a first axis;a plurality of second sensor electrodes oriented substantially parallelto a second axis; and mutual capacitance sensing circuitrycommunicatively coupled to said pluralities of first and second sensorelectrodes and configured to transmit and receive sensing signals onsaid pluralities of first and second sensor electrodes; wherein at leastone sensor electrode of said plurality of first sensor electrodes isdisposed in a configuration forming multiple crossings with a lineparallel to second axis, said multiple crossings occurring proximate toa sensing region of said capacitive input device.
 9. The capacitiveinput device of claim 8, wherein said capacitive input device furthercomprises: a display.
 10. The capacitive input device of claim 9,wherein at least one of said first and second axis is angled withrespect to the display.
 11. The capacitive input device of claim 8,wherein at least one said sensor electrode of said plurality of firstsensor electrodes is configured with a fillable two dimensional areadefined by said at least one sensor electrode.
 12. The capacitive inputdevice of claim 11, wherein said fillable two dimensional area isdefined by said at least one sensor electrode and an extension.
 13. Thecapacitive input device of claim 8, wherein said at least one sensorelectrode of said plurality of first sensor electrodes comprises abounded two dimensional area defined by said at least one sensorelectrode.
 14. The capacitive input device of claim 13, wherein saidbounded two dimensional area is further defined by said at least onesensor electrode, an extension and an extension coupler.
 15. Thecapacitive input device of claim 8, wherein one plurality of saidpluralities of first and second sensor electrodes comprises transmittersensor electrodes and the other plurality of said pluralities of firstand second sensor electrodes comprises receiver sensor electrodes. 16.The capacitive input device of claim 15, wherein said mutual capacitancesensing circuitry is further configured to simultaneously transmitsensor signals on multiple transmitter sensor electrodes of saidplurality of transmitter sensor electrodes.
 17. The capacitive inputdevice of claim 8, wherein at least one sensor electrode of saidpluralities of first and second sensor electrode comprises portions ofdifferent widths.
 18. The capacitive input device of claim 8, whereinsaid at least one sensor electrode comprises substantially the samewidth at locations forming said multiple crossings with a line that isparallel to said second axis.